Process for filling boilers for cellulose with sulphite solution



be a hot solution however the inconv'enience made itself felt, that during the filling Patented Dec. 4, 1928;

e UNITED STATES PATENT OFFICE.

nuts cnmm, or murmur-warmer, gin-Bum, assrenon 'ro znnns'rorrrnnmx wnmmor, or nAmnrn-wnnnor, ennum, n conroRArIoN or GERMANY.

PROCESS. FOR BOILERS IOB CELLULOSE WITH SULPHITE SOLUTION.

Io Drawing. Application filed January 12, 1321, Serial No. 486,851, and in Germany September 4, 1920.

wit the sulphite solution which is required for the boiling process has hitherto been exel outed in such a manner that when the solucellulose.

- tion entered the boiler the air could escape from the same easily and rapidly without the production of a notable pressure in the'boiler. 7 When the filling was eflected with cold 10 solution or with a solution which was only slightly heated, this working method could lied without difiiculty.

1B sulphurous acid separated from the solution which was not absorbed b the wood but escaped fromthe boiler wit the escapin air. Herefrom results that the proportion o sulphurous acid in the solution becomes low, the 0 trituration of the wood being consequently insuflicient.

According to the novel process this difiiculty is overcome by forcin the hot solution. into its boiler with the aid of a pressure 26 pump, the boiler being closed and shut off by means of a safety valve which shuts the-boiler tightly until a certain pressure is attained and then allows the gas or 'air to blow ofi. This safety valve. is adjusted and regulated,

according to the prevalent conditions, spe-,

cially according to the kind of boiling and according to the proportion of sulphurous acid and to the temperature of the solution to be forced in, so that the pressure produced in the boilerleaves, at a determined-"temperature, always suflicient sulphurous acid in-the solution. Thus-it is obtained that also such sulphite solutions which are heated tohigh temperature 900C. and more) can be used'd-irectly and without any difliculty for the filling of boilers for cellulose, this being a great progress in consideration of the utilization of heat in the production of sulphite I claim: 1 t 1. "An improved process for filling cellulose -boilers consisting in forcing heated sulphite liquor by meansof a pressure um mto a closed boiler,-said liquor being '0 sue a cpncfentrlation that it can be used immediate or t e digests 'n o eration. '2? An improved p oc ss for filling cellulose boilers consisting in forcing heated sulhite liquor b' means of a pressure pump mto a boiler c osed u to a certain pressure,

said liquor being 0 such a concentration that it can be used immediately for the digesting operation zj 1 I 3. Any improved process for filling cellulose boilers with hotsulphite liquor, decoma position of said liquor during. preliminary eating havingb'geen revented by suitable means, consisting of orcing said hot-undecomposed sulphite liquor by means of a pressure pump intoja closed boller.

4:. An mproved proces for filling cellulose boilers withhot csulphite liquor, decomposition of said-, liqupr during preliminary heating having been prevented by suitable ,means, consisting of; forcing said hot nudecomposed sulphite 1' nor by means of a pressure pump into a boi or closed up to a certain pressure by an adjustable safety valve.

In testimony-whereofl afiigr my signature. 

